Potential drug treatments for COVID-19 have been in the news for weeks, but if you’ve ignored the headlines to-date, you honestly haven’t missed much. Today’s results on remdesivir are different, though, and there is a lot to unpack here across three separate studies.
Key takeaways from today’s news:
- The NAIAD study results are legitimately encouraging and suggest that administering remdesivir to patients who are hospitalized with COVID-19 can likely save lives.
- At the same time, the efficacy of the drug appears to be modest and its benefit may be limited to only a narrow subset of patients. This may be why the other study of remdesivir published in The Lancet today failed to show similarly encouraging results.
- It is unlikely that remdesivir will substantially alter the optimal approaches to containing the spread of the infection in the workplace or more generally. For example, this news is not the sort of game-changer that would support accelerating plans to open up the economy more quickly or relax social distancing protocols.
What the NAIAD study results say about remdesivir
The full study results have not yet been published, but today’s statement from the NAIAD indicates that remdesivir does appear to help hospitalized patients survive and recover from COVID-19. Specifically, it appears to reduce the length of time patients are hospitalized by roughly 30% and to potentially reduce the rate of mortality among such patients by a similar magnitude. The latter finding is, of course, the most clinically significant but was less definitive from a statistical perspective (specifically, there is a 6% chance the observed difference in mortality was entirely due to random luck).
Why the NAIAD study on remdesivir is more compelling than other drug trials to-date
The NAIAD study is superior to most early studies of potential COVID-19 treatments in that it included a placebo control cohort of members and included a larger number of patients. Until now, encouraging results from other studies have been easy to dismiss because they came from studies that were not placebo-controlled. In a placebo-controlled study, some members are randomly assigned to receive a placebo treatment that does not actually contain the drug of interest. Without a placebo cohort of members, it is very difficult to know whether a high rate of positive outcomes is due to the treatment that was administered or simply means that the members who enrolled in the study were naturally more likely than average to have positive outcomes.
What to make of the other two remdesivir studies released today
The study results released by Gilead, the manufacturer of remdesivir, are not particularly meaningful because it did not include a placebo control arm. As a result, all it can tell us is that treating patients with remdesivir for 5 days vs 10 days does not appear to make much of a difference in positive outcomes and/or adverse event rates.
The study published in The Lancet today is a bit more interesting, but is also hard to draw conclusions from. While the study observed a somewhat faster time to clinical improvement with remdesivir, as compared to placebo, this difference was not statistically significant. This lack of statistical significance may be a byproduct of the study enrolling fewer patients than the NAIAD study and/or the fact the study focused on more severe cases (i.e., patients on mechanical ventilation). That said, the lack of clear positive results from this study do suggest that the drug is not a miracle cure (if it was, then the sample size of the study would have been sufficient to show a significant impact) and may be unable to make much of a difference for patients who have already progressed to the point of needing a ventilator.
What to expect moving forward
There are a number of ongoing trials for remdesivir that will hopefully tell us a lot more about its ability to combat COVID-19. At this point it’s fair to say the drug probably does improve hospitalized patients’ chances of surviving the virus, but it’s also fair to say it probably won’t be enough to save the majority of patients. As a result, this news is not the sort of game-changer that would support accelerating plans to open up the economy more quickly or relax social distancing protocols. It’s a big deal and we should be encouraged by the findings, but the virus remains just as infectious as ever and very deadly to some who contract it.